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Resilient engineering design initiative for floods

Recent increases in the prevalence of extreme weather events significantly impact the annual cost of flood-related losses, both insured and uninsured. The development of a well-vetted industry tool to evaluate potential losses should provide clear financial planning options for owners, insurers and agencies providing emergency assistance.

An obstacle in promoting reduced flood risk is a lack of knowledge on the part of key stakeholders (typically owners, developers, local and national government and the citizens who live and work in the affected communities) as to the consequences of a code-based approach to flood design. If left unaware of these consequences, stakeholders may not have enough information to make critical decisions to reduce flood risk to their property, businesses and communities.

To address these concerns, this project developed a framework for implementing resilience-based flood design to promote and incentivize ‘beyond code’ flood resilience goals. The framework is based on the existing Resilience-based Design Initiative (REDi™) rating system that was developed for assessing resiliency to earthquake hazards (available online). REDi™ for flooding forms an additional assessment module that complements the established REDi™ seismic rating system, adding further traction to the resilience-based design approach.

The REDi™ tool for flooding facilitates communication of flood risk to owners and other stakeholders, and provides them with an overview of design and planning criteria to help reduce financial loss and to enable rapid resumption of facility operations after a flood event.

The REDi™ approach has been recognized by the US Green Building Council as a method for achieving Resilient Design LEED Pilot Credits.

In applying the REDi™ approach to flooding, the assessment tool distinguishes between the expected downtime of the building as a usable facility following a flood event: a flood-resistant design allows immediate occupation and use after a flood; a flood-resilient design requires some clean up but no physical repair after a flood; and a repairable design involves several months of downtime after a flood, before the building can be reoccupied.

 

 

The REDi™ assessment of flood resiliency is implemented via a spreadsheet based tool.  REDi™ provides a consistent, resilience-based approach for use by architects, owners and engineers to achieve 'beyond life-safety' resilience objectives for flood hazards to buildings.

 

The outcome of our project fills a major gap in what modern building codes provide and what the public and private sectors desire in terms of post-disaster recovery.

REDi™ provides a tool to communicate with a building's owner and the rest of the design team the expected flood resilience performance of the building, the design and planning measures required to achieve rapid functional recovery objectives, and a consistent basis for these stakeholders to be involved throughout the design process in relation to flood resilience.